Role of Aldynoglia Cells in Neuroinflammatory and Neuroimmune Responses after Spinal Cord Injury

Abstract

Aldynoglia are growth-promoting cells with a morphology similar to radial glia and share properties and markers with astrocytes and Schwann cells. They are distributed in several locations throughout the adult central nervous system, where the cells of the aldynoglia interact and respond to the signals of the immune cells. After spinal cord injury (SCI), the functions of resident aldynoglia, identified as ependymocytes, tanycytes, and ependymal stem cells (EpSCs) of the spinal cord are crucial for the regeneration of spinal neural tissue. These glial cells facilitate axonal regrowth and remyelination of injured axons. Here, we review the influence of M1 or M2 macrophage/microglia subpopulations on the fate of EpSCs during neuroinflammation and immune responses in the acute, subacute, and chronic phases after SCI.

Mechanism Underlying Acupuncture Therapy in Spinal Cord Injury: A Narrative Overview of Preclinical Studies

“…The pro-inflammatory macrophage/microglia (M1 subsets) and anti-inflammatory macrophage/microglia (M2 subsets) are significant. Therefore, regulating the polarization of M1 and M2 macrophages/microglia can affect the inflammatory response process after SCI ( Buzoianu-Anguiano et al, 2021 ; Ding et al, 2021 ; Hashemizadeh et al, 2022 ). Previous studies have shown that acupuncture can ameliorate SCI by regulating M1 and M2 macrophages ( Zhao et al, 2017 ).…”

The Immunological Roles of Olfactory Ensheathing Cells in the Treatment of Spinal Cord Injury

“…The regenerative capacity of the adult mammalian spinal cord after injury is extremely limited, mainly due to multifaceted adverse factors in addition to inflammatory cell activation that together contribute to a non-permissive environment and minimal functional recovery ( 1 , 16 , 160 , 161 ). Neuroinflammation is part of the primary responses to injury and might be linked to the characteristics of innate immune cells and immunological molecules involved in the injury area ( 19 , 162 , 163 ).…”

“…Once OECs are implanted into the injured spinal cord zone, numerous molecules released from OECs, as acute positive and negative regulators participate in modulating the expression and activity of cytokines and chemokines ( 167 ). For instance, the anti-inflammatory cytokines IL-4, IL-10, TGF-β, and IL-13 produced by OECs protect against cell degeneration or death by modulating iNOS and NO production in the context of LPS/IFN-γ stimulation ( 90 , 158 , 159 , 161 ). Meanwhile, these anti-inflammatory cytokines are indicative of inhibition of the release of the pro-inflammatory cytokines TNF-α, IL-1β, IL-2, and IL-6 ( 161 , 165 ).…”

“…For instance, the anti-inflammatory cytokines IL-4, IL-10, TGF-β, and IL-13 produced by OECs protect against cell degeneration or death by modulating iNOS and NO production in the context of LPS/IFN-γ stimulation ( 90 , 158 , 159 , 161 ). Meanwhile, these anti-inflammatory cytokines are indicative of inhibition of the release of the pro-inflammatory cytokines TNF-α, IL-1β, IL-2, and IL-6 ( 161 , 165 ). As a consequence, OECs delay the activation of microglia/macrophages, the time-dependent multiphasic inflammatory response, and the peak of the immune response, leading to neuroprotection against further inflammatory damage ( 26 , 29 , 35 , 63 , 112 , 167 ).…”

The Function of Glial Cells in the Neuroinflammatory and Neuroimmunological Responses

“…The existence of structural and functional diversity within the glial population explains the diverse roles played by these cells in a region-specific manner. In their review, Buzoianu-Anguiano et al shed light on molecular and functional aspects of a group of glial cells, collectively named aldynoglia [ 8 ]. They further extended their discussion to the regenerative potential of aldynoglia in spinal cord injury and suggested many mechanisms by which these cells can be used as therapeutics in spinal cord injury.…”